An abscess is an infection characterized by a collection of pus underneath a portion of the skin. Bacteria commonly causing abscesses are Staphylococcus aureus and Streptococcus. These bacteria enter the skin through any cracks or injury to the skin. That area of skin then becomes red, tender, warm, and swollen over days to 1–2 weeks and a fever may develop. Abscesses can sometimes form if minor superficial skin infections are not treated appropriately and in a timely fashion. Most abscesses resolve quickly once appropriately treated.
Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is a strain of "staph" bacteria resistant to antibiotics in the penicillin family, which have been the cornerstone of antibiotic therapy for staph and skin infections for decades. CA-MRSA previously infected only small segments of the population, such as health care workers and persons using injection drugs. However, CA-MRSA is now a common cause of skin infections in the general population. While CA-MRSA bacteria are resistant to penicillin and penicillin-related antibiotics, most staph infections with CA-MRSA can be easily treated by health care practitioners using local skin care and commonly available non-penicillin-family antibiotics. Rarely, CA-MRSA can cause serious skin and soft tissue (deeper) infections. Staph infections typically start as small red bumps or pus-filled bumps, which can rapidly turn into deep, painful sores. If you see a red bump or pus-filled bump on the skin that is worsening or showing any signs of infection (ie, the area becomes increasingly painful, red, or swollen), see your doctor right away. Many patients believe incorrectly that these bumps are the result of a spider bite when they arrive at the doctor's office. Your doctor may need to test (culture) infected skin for MRSA before starting antibiotics. If you have a skin problem that resembles a CA-MRSA infection or a culture that is positive for MRSA, your doctor may need to provide local skin care and prescribe oral antibiotics. To prevent spread of infection to others, infected wounds, hands, and other exposed body areas should be kept clean and wounds should be covered during therapy.
Factors that predispose individuals to developing an abscess include:
- Any skin infection, especially those that are untreated
- Intravenous drug abuse
- Weakened immune system due to underlying illness or medication
Abscesses can occur in anyone and occur anywhere on the body.
You might be able to sense fluid in an abscess when you press on the abscess with a finger.
A worsening red, tender swelling that arises over a period of 1–2 weeks. The pus underneath the skin is usually not visible. You may have a fever or a general sense of not feeling well.
There are no self-care options for abscesses. While waiting to see your doctor, you can try applying a warm compress to the affected area and take ibuprofen to help with the swelling and pain.
A worsening red, tender swelling should prompt you to make an appointment with your physician as soon as possible. If the area involves your face, is spreading rapidly, or is in an area that severely limits your functionality, you should seek emergency care.
Your doctor may drain the pus and fluid collection by making a small incision in the skin after it has been numbed. This will drain a majority of the bacteria, helping the body fight the small amount that remains. This fluid may then be sent to a laboratory for testing (culture), but not necessarily. The culture can tell the doctor not only what type of bacterium is causing the infection but also what antibiotics will work best to treat it. This may take as little as 2–3 days. Your doctor may choose to have you start oral antibiotics aimed at treating the most common bacteria that cause abscesses while awaiting these results. However, if the infection is small and it has been drained, your doctor may decide to not treat you with oral antibiotics.
If your symptoms are not improving or it is determined that the bacterium is not one of the common types, your doctor may prescribe different antibiotics. If your doctor prescribes antibiotics, it is important to take the entire course as prescribed, even if you are feeling better or the infection appears to be gone after just a few days. If you have been taking antibiotics and the infection itself or the way you are generally feeling have not improved in about 2–3 days, return to see your doctor.